The problem of designing a feedback system with prescribed properties is attacked via a fractional representation approach to feedback system analysis and synthesis. To this end we letHdenote a ring of operators with the prescribed properties and model a given plant as the ratio of two operators inH. This, in turn, leads to a simplified test to determine whether or not a feed...
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The paper presents a proof of stability of model reference adaptive control systems using direct control. The structure of the adaptive system is similar to that considered by Monopoli [1] and Narendra and Valavani [2] but contains an additional feedback term which ensures that the time derivative of the parameter error vector belongs to the L2space. The output of the plant is shown to ...
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A process exhibits a deadbeat response when the error between input and output is reduced to zero in finite time. In this Paper design procedures for state feedback and minimal energy dynamic deadbeat controllers are presented. These controllers reduce the error between step input and output to zero, while at the same time assuring that the continuous system is in steady state. The resulting multi...
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In this paper, we study the problem of stabilizing a nonlinear control system by means of a feedback control law, in cases where the entire state of the system is not available for measurement. The proposed method of stabilization consists of three parts: 1) determine a stabilizing control law based on state feedback, assuming the state vectorx(t)can be measured; 2) construct a state de...
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This paper presents new results on the so-called constrained controllability problem. Attention is focused upon the problem of steering the statex(t)of the systemdot{x}(t)=A(t)x(t)+ f(t,u(t))to a prescribed closed, convex target setX.The inputu(t)is restricted to a prescribed compact set Ω. In contrast to the existing literature, our criteria for co...
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The behavior of solutions of a class of large-scale systems with the bounded coefficients of the form [1] has been studied. The functionV_{i}(x_{i},t)=A_{i}(t)x_{i}^{2}, whose coefficientA_{i}(t)is bounded for allt geq 0, gives the conditions on the Lyapunov function such that the system (1) is either asymptotically stable or unstable. Since the function of the for...
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Assuming that the solution of the autonomous Riccati differential equation exists for allt geq 0, we give a necessary and sufficient condition for the solution to be periodic. At the same time, from this condition one can readily obtain the period of this periodic solution. Similar results are shown for the discrete and nonautonomous Riccati equations.
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Generation of one of the auxiliary inputs in model reference adaptive control systems requires a positive definite quadratic function of2nsystem variables for annth order system. To generate such a function can require as many as2nsignal multiplications. In this paper, it is shown how this input can be replaced by one that is much simpler to generate and reduces th...
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In this paper the phasor analysis of the notch filter using adaptive canceling of sinusoidal interferences is given. Amplitude and phase characteristics are very clearly presented by phaser especially when the phase between reference signals is not exactlypi/2. Because of the output signal pulsation occurring in this case every other analysis is too complicated. This is a new approach a...
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A simple error model is described for both discrete and continuous time adaptive systems. The stability of the model for both bounded and unbounded inputs is analyzed for the discrete case and extended to continuous time models. It is shown thatDeltaphi(k)in I^{2}in the former case andphi(t)in L^{2}in the latter case due to the presence of a feedback signal and these in turn ...
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The purpose of this correspondence is to point out a "noncausal" property of reproducing kernel Hilbert spaces which vitiates much of the argument of the above paper. It is, however, argued that the results claimed in the paper are nevertheless substantially correct.
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The decentralized system in the above paper can be reduced to a simpler system, which achieves the same goal but with less computations. The new system is obtained by a straightforward decomposition of the Kalman filter.
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This correspondence shows how a nonrecursive solution of the discrete matrix Riccati equation can be obtained when, in contrast with the assumption of Vaughan [1], the transition matrix is singular and discusses two numerical solution techniques.
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A new stability criterion of composite systems is applied to multimachine power systems. This criterion has advantage in evaluating the influence of the interaction by bilinear forms. In the examples, it is shown that the range of the values of parameters for which the new method can assure stability is considerably wider than that obtained by the Jocić et al. method.
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A representation is presented for the general solution of the homogeneous linear matrix differential equation system. The representation derived is then used to describe the dynamic behavior of the matrix system in terms of the properties of constituent systems of lower order.
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It is shown that time-delay action can be used in the design of controllers having quick settling-time property. Specifically, when the feedback compensator is implemented by means of proportional minus delay action, the output performance of the closed-loop system can be better in the sense of ITAE index than that of the system which employs a conventional proportional-plus-derivative action. For...
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Aims & Scope

In the IEEE Transactions on Automatic Control, the IEEE Control Systems Society publishes high-quality papers on the theory, design, and applications of control engineering. Two types of contributions are regularly considered